Photoshop

by Adobe

Photoshop is a full featured photo and graphic editor. It is one of the most popular photo editing software programs in the art industry. You can work with bitmap and vector graphics, making this program ideal for both drawings and photographs.

Photoshop is a very large program with every feature imaginable. I think they left out something as simple as underlined text for a while, but that has been taken care of. There is no image editing software more powerful than Adobe Photoshop. I see a lot of imitators with similar names.
Print Shop is one example that comes to mind. Adobe Photoshop is the brand name for image and photo editing.